In general, a vehicle door representative of a vehicle includes an door outer panel at an exterior side and an door inner panel at an interior side, which are arranged to face each other with a window plate (window glass) being interposed therebetween, and a decorative door trim is arranged at the interior side of the door inner panel. A weather strip serving as a seal material is arranged at a beltline along a lower edge of a window opening edge of the door, and a glass run channel is arranged at the other window opening edges. The weather strip includes an outer weather strip, which is mounted to an upper edge flange of the door outer panel, and an inner weather strip, which is mounted to an upper edge flange of the door inner panel. The glass run channel is arranged along the window opening edge, and has an upper edge portion configured to accommodate therein the window plate having moved up and a window plate guide part extending in an upper and lower direction along an up-and-down locus of both edges of the window plate so as to guide an up-and-down operation of the window plate.
The door outer panel is provided at its lower part with an opening (drain hole) for discharging rain and the like, which flows into the door from a region between the door outer panel and the window plate, to an outside of the door. Also, the door inner panel is provided with an opening for mounting therein a door handle, a window regulator and the like. For this reason, an exterior noise such as a road noise, a wind noise and the like during traveling is introduced into the door through the door outer panel itself, particularly the lower opening, so that a passenger in a vehicle interior may hear the exterior noise.
As routes through which the exterior noise introduced into the door is introduced into the vehicle interior, three routes can be representatively exemplified, as follows.
First route: A route through which the exterior noise passes through the opening provided in the door inner panel and through the door trim to be introduced into the vehicle interior.
Second route: A route through which the exterior noise passes through a gap between the window plate and the door inner panel to be introduced into the vehicle interior.
Third route: A route through which the exterior noise passes through the opening provided in the door inner panel and passes a gap between the door inner panel and the door trim to be introduced into the vehicle interior from a gap between the inner weather strip and the door trim.
Therefore, as a sound insulation means for the exterior noise which passes through the above-described routes, generally, the following measures have been taken. Regarding the first route, the door trim is provided with a sound-absorbing material. Regarding the second route, the inner weather strip mounted to the door inner panel is provided with a seal lip, and the seal lip is elastically contacted to the window plate to block the gap. Regarding the third route, the inner weather strip mounted to the door inner panel is provided with a top wall lip, and the top wall lip is elastically contacted to the door trim to block the gap.
For example, JP-A-2004-74830 discloses an inner weather strip that is to be used for the measures of the second and third routes. The inner weather strip is a long member that is mounted to the interior beltline of the vehicle door having the window plate. At a state where the inner weather strip is mounted to the beltline, both longitudinal direction end portions of the inner weather strip is in contact with the glass run channel, which is mounted in the upper and lower direction along the up-and-down locus of both edges of the window plate so as to guide an up-and-down operation of the window plate. Specifically, the inner weather strip has a main body part having an exterior lateral wall and an interior lateral wall, which are arranged to face each other with a predetermined interval, and a top wall integrally connecting upper edges of both lateral walls. Also, an outer surface of the exterior lateral wall is provided with an upper seal lip and a lower seal lip, each of which having a pleat shape and elastically contacting the window plate. The upper seal lip and the lower seal lip extends between both longitudinal direction end portions of the exterior lateral wall. Also, an outer surface of the top wall is provided with a top wall lip, which has a pleat shape and elastically contacts the door trim. The top wall lip extends between both longitudinal direction end portions of the top wall.